/* $OpenBSD: mk_priv.c,v 1.6 1998/05/18 00:53:51 art Exp $ */ /* $KTH: mk_priv.c,v 1.20 1998/02/19 19:13:40 joda Exp $ */ /* * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska H�gskolan * (Royal Institute of Technology, Stockholm, Sweden). * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the Kungliga Tekniska * H�gskolan and its contributors. * * 4. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "krb_locl.h" /* application include files */ #include "krb-archaeology.h" /* * krb_mk_priv() constructs an AUTH_MSG_PRIVATE message. It takes * some user data "in" of "length" bytes and creates a packet in "out" * consisting of the user data, a timestamp, and the sender's network * address. * The packet is encrypted by pcbc_encrypt(), using the given * "key" and "schedule". * The length of the resulting packet "out" is * returned. * * It is similar to krb_mk_safe() except for the additional key * schedule argument "schedule" and the fact that the data is encrypted * rather than appended with a checksum. The protocol version is * KRB_PROT_VERSION, defined in "krb.h". * * The "out" packet consists of: * * Size Variable Field * ---- -------- ----- * * 1 byte KRB_PROT_VERSION protocol version number * 1 byte AUTH_MSG_PRIVATE | message type plus local * HOST_BYTE_ORDER byte order in low bit * * 4 bytes c_length length of data * we encrypt from here with pcbc_encrypt * * 4 bytes length length of user data * length in user data * 1 byte msg_time_5ms timestamp milliseconds * 4 bytes sender->sin.addr.s_addr sender's IP address * * 4 bytes msg_time_sec or timestamp seconds with * -msg_time_sec direction in sign bit * * 0<=n<=7 bytes pad to 8 byte multiple zeroes */ int32_t krb_mk_priv(void *in, void *out, u_int32_t length, struct des_ks_struct *schedule, des_cblock *key, struct sockaddr_in *sender, struct sockaddr_in *receiver) { unsigned char *p = (unsigned char*)out; unsigned char *cipher; struct timeval tv; u_int32_t src_addr; u_int32_t len; if (p == NULL) return 0; p += krb_put_int(KRB_PROT_VERSION, p, 1); p += krb_put_int(AUTH_MSG_PRIVATE, p, 1); len = 4 + length + 1 + 4 + 4; len = (len + 7) & ~7; p += krb_put_int(len, p, 4); cipher = p; p += krb_put_int(length, p, 4); memcpy(p, in, length); p += length; krb_kdctimeofday(&tv); *p++ =tv.tv_usec / 5000; src_addr = sender->sin_addr.s_addr; p += krb_put_address(src_addr, p); p += krb_put_int(lsb_time(tv.tv_sec, sender, receiver), p, 4); memset(p, 0, 7); des_pcbc_encrypt((des_cblock *)cipher, (des_cblock *)cipher, len, schedule, key, DES_ENCRYPT); return (cipher - (unsigned char*)out) + len; }